#16252: QuantifiedConstraints: lack of inference really is a problem -------------------------------------+------------------------------------- Reporter: lightandlight | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.6.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by lightandlight): Okay, I've thought about this for a little bit: Why shouldn't the implication constraint be considered part of `quant_pred_candidates`? It seems to me that the error is in discarding it as a candidate in the first place. In other words, I would expect `g`'s inferred type to be `(forall x. Eq x => Eq (f x)) => A f -> A f -> Bool`. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/16252#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler